The senses of taste, hearing, and touch also involve complex processes of stimulation of receptor
cells along with neural encodings and transformations. Similarly, the perception of pain, temperature,
balance, and internal states such as gastrointestinal fullness are increasingly well understood in terms
of how dedicated brain areas interpret signals from various kinds of receptors. Some animals have
sense receptors not found in humans—for example, those that enable some fish to detect electric
fields. Although there is still much that is unknown about how brains perceive sights, smells, and
other sensations, neural explanations of perception are sufficiently rich to justify thinking of
perception as a collection of different kinds of brain processes. Chapter 4 discusses further how
brains perceive the world.